Chemical Nomenclature 1. Binary Ionic Compounds - Type I 2. Binary Ionic Compounds - Type II 3. Ionic Compounds & Polyatomic (Complex) Ions 4. Hydrated Ionic Compounds 5. Binary Covalent Compounds

Definitions n An IONIC COMPOUND consists of a metal cation bonded to a nonmetal anion. Electrostatic attraction holds them together. n A COVALENT COMPOUND consists of two nonmetal atoms sharing valence electrons. n A BINARY compound is one that is made of just two elements.

Type I Binary Ionic Compounds n The metal cations in these compounds have only ONE possible charge. Na + Zn 2+ Al 3+ Ca 2+ sodiumzinc aluminumcalcium The charges are predicted using a periodic table! n These are bonded to nonmetal anions: O 2 - N 3 - F - Br - oxide nitride fluoride bromide Notice that simple anions are always named with the suffix “ide”

n In an ionic compound, the charges of the cations and anions must always cancel out. n Subscripts are used if more than one atom is needed to cancel the charges: sodium chloride: Na + and Cl -  NaCl lithium oxide: Li + and O 2-  Li 2 O aluminum bromide: Al 3+ and Br -  AlBr 3 zinc nitride: Zn 2+ and N 3-  Zn 3 N 2 potassium iodide: K + and I -  KI silver phosphide: Ag + and P 3-  Ag 3 P

Examples: Type I Binary Ionic Compounds Write the formulas: potassium oxide zinc chloride silver sulfide aluminum nitride gallium oxide calcium iodide Write the names: K 3 N AgI ZnBr 2 Al 2 O 3 Ba 3 P 2 LiH

Type II Binary Ionic Compounds n These are ionic compounds where the metal cation can form TWO different charges. Fe 2 + iron (II) Fe 3 + iron (III) Ni 2 + nickel (II) Ni 3 + nickel (III) Co 2 + cobalt (II) Co 3 + cobalt (III) Cu + copper (I) Cu 2 + copper (II) Au + gold (I) Au 3 + gold (III) Sn 2 + tin (II) Sn 4 + tin (IV) An older system uses suffixes and Latin names, - ous for the lower charge, - ic for the higher charge: Ferrous & Ferric, Cuprous & Cupric, Stannous & Stannic

Examples: Type II Binary Ionic Compounds Write the formulas: iron (II) oxide copper (II) chloride tin (IV) sulfide cupric nitride nickel (III) oxide ferrous iodide cobalt (III) selenide Write the names: Fe 2 O 3 SnS NiBr 2 CuS Pb 3 P 2 CuBr FeCl 3

Polyatomic (Complex) Ions n All of the cations and anions so far have been simple ions - single atoms that have lost or gained electrons. n A molecule is a particle that forms when two or more atoms bond together. n A complex ion is a charged molecule. Complex ions may be cations or anions. examples: nitrate: NO 3 - sulfate: SO hydroxide: OH -

Writing formulas with Complex Ions a) Ammonium chlorideNH 4 Cl b) Silver sulfateAg 2 SO 4 c) Aluminum hydroxideAl(OH) 3 d) Calcium phosphateCa 3 (PO 4 ) 2 e) Iron (III) nitriteFe(NO 2 ) 3 f) Copper(II) permanganateCu(MnO 4 ) 2 g) Ammonium dichromate(NH 4 ) 2 Cr 2 O 7 h) Zinc acetateZn(CH 3 COO) 2

Things to Notice n Most complex ions are anions. Ammonium, NH 4 +, is the most common complex cation. n Several complex ions form a short series of ions. The ions differ only in the number of oxygen atoms: perchorateClO 4 - sulfateSO 4 2- chlorateClO 3 - sulfiteSO 3 2- chloriteClO 2 - hypochloriteClO - nitrateNO 3 - nitriteNO 2 -

n If an ion carries a charge like “-2” or “-3”, a series of related ions can be formed by adding hydrogen cations (H + ) while still leaving a net charge: examples: Sulfide:S 2- hydrogen sulfide:HS - (bisulfide) Sulfate:SO 4 2- hydrogen sulfate:HSO 4 - (bisulfate) Carbonate:CO 3 2- hydrogen carbonate:HCO 3 - (bicarbonate) Phosphate:PO 4 3- hydrogen phosphate:HPO 4 2- dihydrogen phosphate:H 2 PO 4 -

More Formulas with Complex Ions a) Sodium bicarbonateNaHCO 3 b) Nickel (II) hydrogen sulfideNi(HS) 2 c) Aluminum perchlorateAl(ClO 4 ) 3 d) Barium dihydrogen phosphateBa(H 2 PO 4 ) 2 e) Iron (III) sulfiteFe 2 (SO 2 ) 3 f) Cuprous bisulfateCuHSO 4 g) Zinc periodateZn(IO 4 ) 2 h) Lithium seleniteLi 2 SeO 3

Binary Covalent Compounds n Covalent compounds are made of two NONMETAL elements sharing valence electrons. n There are no ions involved!! n Because there are no charges to help us write the formulas of covalent compounds, prefixes are used to indicate the number of each atom present in the formula. CO 2 is named “carbon dioxide” CO is named “carbon monoxide” N 2 O is named “dinitrogen monoxide” SO 3 is named “sulfur trioxide” The prefix, “mono” is never used for the first element in the formula!

Examples of Covalent Naming n Write the names: SO 2 sulfur dioxide P 4 O 10 tetraphosphorus decoxide n Write the formulas: phosphorus pentachloridePCl 5 dinitrogen trioxideN 2 O 3